Thunderbird and Firefox are separate programs. A problem with one should not affect the other.

Please explain the problem in detail. What happens? What is/are the exact error message(s) ?

What were you doing step by step?

Fred, Thanks for your reply. I was able to use M/S EDGE to get this done. Now today I had the same problem trying to execute another EXE file that I just downloaded. Each time I try to execute the downloaded file, Firefox hangs up and I need to use Task Manager to cancel it and start over. Once again, I used EDGE to get the job done. Quite annoying to say the least. Thanks in advance. Jim

It just occurred one more time. I download an EXE file for the AVAST program and then tried to execute it. Firefox just freezes.

I think what you are trying to say is that Firefox is freezing when downloading a file/program. Yes?

Running anything else should not freeze the browser. Including an installer for something else.

I know what you're saying that the install programs are separate from Firefox but it very consistent. It has happened trying to execute 3 separate downloads. It does not happen with M/S EDGE. How can I elevate this issue with Mozilla Support? Thanks again. Jim

Okay. You are trying to download. Not run a program.

Have you had a window come up saying Firefox had crashed?

Is this with all websites/pages, some, a few?

Start Firefox using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh). Is the problem still there?

Go to the Mozilla Add-ons Web Page {web Link} (There’s a lot of good stuff here) and search for a download manager.

This download manager works separately from the browser. The browser tells it what to download, and off it goes.

http://www.freedownloadmanager.org It is a powerful modern download accelerator and organizer for Windows and Mac.

Fred, The problem is not in the download process. That works just fine. It is when I try to execute the downloaded programs that Firefox hangs. I just tried Firefox in Troubleshoot mode several times - same result.

I have the same problem right now when I downloaded and tried to run 'Download Manager'. Firefox freezes.

okay, now I got it. As I said before, this should not happen.

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

https://support.mozilla.org/en-US/kb/firefox-takes-long-time-start-up

https://support.mozilla.org/en-US/kb/quick-fixes-if-your-firefox-slows-down

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-or-cpu-resources

MemTest LAST UPDATED : 12/04/2020 Could you please run a tool from http://memtest.org/ in order to check the integrity of your RAM?

You will need a thumb or disk drive to install it on.

Do you let Windows handle the page file or did you set a fixed size ? Control Panel -> System -> Advanced -> Performance -> Settings

If you use a fixed size for the page file then try the former and let Windows handle the page file. How to determine the appropriate page file size for 64-bit versions of Windows {web link}

Fred, Some more data. I did a 'Refresh' on Firefox. That did not solve the problem. I wonder if a complete new install of Firefox will fix it.

I still have my previous laptop. I started it up this morning and Firefox had absolutely no problems with executing 5 downloaded programs. I will have to use my old laptop for now.

Sidenote: You know that M/S EDGE has this function called 'Smartscreen'. Well it blocks almost everything I try to download/execute on my new laptop. On my old laptop, EDGE Smartscreen does not block anything. These could be Windows 10 problems and not related to Firefox or Edge. The MEMTEST.Org tool would have to be downloaded and I can't do that.

M/S EDGE has this function called 'Smartscreen'. Well it blocks almost everything I try to download/execute on my new laptop.

You should try asking about that here: https://support.microsoft.com

http://answers.microsoft.com/en-US/windows/forum/windows_10

Fred, I did a factory reset and that solved the problems. Thank you so much for your time and expertise. Jim

That was very good work. Well Done. Please flag your last post as Solved Problem as this can help others with similar problems. Go to that post and click the 'Solved' button to its right.